Mechanism of synthesis of hydrocarbons, from fatty acids, will be elucidated in cell-free preparations. The goal is to provide the biochemical understanding of this process which occurs in all living cells and has been implicated in many disorders including disfunction of the nervous system. The structure and function of fatty acid synthase, the key enzyme involved in fat synthesis in animals, will be studied using techniques of protein chemistry. Biochemical mechanisms which determine the size of the fatty acids generated in specialized tissues such as sebaceous glands will be studied using avian uropygial glands as a model system. Mechanism of synthesis of alkane-1,2-diols, alkane-2,3-diols and diesters of hydroxy acids will also be studied using subcellular fractions from sebaceous glands. mechanism of synthesis of 2-methyl, 3-methyl and 4-methyl branched acids from branched precursors will be studied using enzyme preparations from uropygial glands. Enzymology of synthesis of multiple methylbranched aglycone of macrolid antibiotics will be studied in cell-free preparations from Streptomyces erythreus. Biosynthesis of multiple methyl branched mycocerosic acids, characteristic of Mycobacterium tuberculosis, will be elucidated with cell-free preparations. The source of the precursors for the branched natural products will be examined. The relationship between the cytoplasmic and mitochondrial malonyl-CoA decarboxylase, a key regulatory enzyme, and the synthesis of this enzyme will be elucidated. Regulation of lipid metabolism in sebaceous glands will be studied using the uropygial gland as the model system.